Performance has been an important issue with Java™ since the first version hit the Web years ago. Making those first interpreted programs run fast enough was a huge challenge for many developers. Since then, Java performance has improved enormously, and any Java program can now be made to run fast enough provided you avoid the main performance pitfalls.
This book provides all the details a developer needs to performance-tune any type of Java program. I give step-by-step instructions on all aspects of the performance-tuning process, right from early considerations such as setting goals, measuring performance, and choosing a compiler, to detailed examples on using profiling tools and applying the results to tune the code. This is not an entry-level book about Java, but you do not need any previous tuning knowledge to benefit from reading it.
Many of the tuning techniques presented in this book lead to an increased maintenance cost, so they should not be applied arbitrarily. Change your code only when a bottleneck has been identified, and never change the design of your application for minor performance gains.
Chapter 1 gives general guidelines on how to tune. If you do not yet have a tuning strategy, this chapter provides a methodical tuning process.
Chapter 2 covers the tools you need to use while tuning. Chapter 3 looks at the Java Development Kit™ ( JDK, now Java SDK), including VMs and compilers.
Chapter 4 through Chapter 12 cover various techniques you can apply to Java code. Chapter 12 looks at tuning techniques specific to distributed applications.
Chapter 13 steps back from the low-level code-tuning techniques examined throughout most of the book and considers tuning at all other stages of the development process.
Chapter 14 is a quick look at some operating system-level tuning techniques.
Each chapter has a performance tuning checklist at its end. Use these lists to ensure that you have not missed any core tuning techniques while you are tuning.